Method of and apparatus for making honeycomb material



R. C. STEELE Sept. 16, 1952 METHOD OF AND APPARATUS FOR MAKING HONEYCOMB MATERIAL Filed Nov. 22, 1948 5 Sheets-Sheet 1 K W n,

R 08 m 5 0 8 my 6 w Y 4 J 00 H /m /o a v l F 5 a a L y A 2 z 4% 5 5 9 M .w a r b e 9 I 0. 1 1 1 m /o 2 3 5 Z uvfi l I 4 I. In" .IIIIIPI .M 5 Y I. llll ll UT 0. 9 I. II II ll| E II II III a 7 n 2 Z 0 5 4 5 3 I. 5 1 4 a Z 3 Z I 1. 3 z u 1|! 8 6 5 6 7 4 nu M Z 5 4 Z Y 5 4 5 M Sept. 16, 1952 R. c. STEELE 2,610,934

METHOD OF AND APPARATUS FOR MAKING HONEYCOMB MATERIAL Filed Nov. 22, 1948 3 Sheets-Sheet 2 I N VEN TOR.

@065? as a; BY M ATTORNEY Sept. 16, 1952 R. c. STEELE ,5

METHOD OF AND APPARATUS FOR MAKING HONEYCOMB MATERIAL Filed Nov. 22, 1948 3 Sheets-Sheet 3 I N VEN TOR.

jaw/{$0114 ATTORNEY Patented Sept. 16, 1952 UNITED STATES PATENT OFFICE] Roger "0. Steele, Oakland, Calif., assignor to California Reinforced Plastics Company, Berkeley,

Calif.

Application November 22, 1948, Serial No. 61,352

' :13 cl ms. (01.154 13) This invention relates to an improved method and machine for making a honeycomb structure out of an elongated sheet of flexiblematerial.

It has been found that use of a honeycomb or cellular core in laminated panel, wall bulkhead or fuselage structure makes it possible to produce such products which are not only extremely light in weight but which are characterized by their great structural strength and rigidity.

A principal object, therefore, of the present invention is to provide a, method and a machinefor making honeycomb out of an elongated sheet of flexible material, ,such as paper, aluminum foil, cloth, fabric, glass cloth, or the like in substantially one continuous operation. I M 4 The present invention comprises; generally a machine having means to apply substantially parallel and uniform glue lines to an elongated sheet of material and to furtherprovide meansto lap said glued material back and forth over itself in superposed layers to form a, stack of layers which may be sliced into smaller pieces and expanded to form a honeycomb structure which is characterized by its uniformity in cellsize and shape. Another object of this invention isto provide a machine which is capable of making large quantities of unexpanded honeycomb material from elongated sheets of flexible material in one sub- -stantially continuous-operation and employing a minimum of hand labor. I Another object of this invention is to provide a machine for making honeycomb of the type above referred to which said machine is provided with novel means-to maintain-astack of superposed loyers of glued material tightly compressedtof gether during lapping operations to prevent undesirable wrinkles or creases being formed in said material' 1 j A further object of a machine for making honeycomb which is relatively inexpensive to manufacture, is of sturdy construction and is relatively simple to install and operate. i j 1 v I Otherobjects of this invention will become ap-,- parent upon reading" the following'spe'cification and referring to the'accompanying drawings, in which similar characters of reference represent corresponding parts in each of ,the'lseveral views. In the drawings: T f Fig. 1 is a perspective view of the machine. Fig. 2 is a side elevational view of the machine. Fig. 3 is an end elevational view of the machine. Fig. 4 is a'view, taken along line 4-4 of Fig. 2, showing parts'p'artially broken away in section. Fig. 5 is an enlarged fragmentaryview of parts his'invention is to provide of the driving and compressing mechanism of the machine. v r

Fig. 6 is an exploded view, showing the manner in which the material is lapped over itself in the machine and the relative positions of the glue lines.

Fig. '7 illustrates the manner in whichstacks of superposed layers of glued material may be sliced and expanded to form a honeycomb structure.

The apparatus to be described herein incorporates alarge number of rotating or rotatably mounted shafts or rollers and all of which, for purposes of simplicity and clarity in illustration, are not shown as being visibly supported by suitable bearings and the like. It will suffice, for the proper understanding of this invention, to relate merely that wherever such shafts are indicated andid entified it is understood that inactual con struction of the machine such parts would normally be supported appropriatelyby suitable conventional bearings. Th particular type of bearings employed constitutes no part efthe present n nt Referring now to certain principal parts of the machine which-are indicated generally,- the general principles of operation underlying my method and-apparatus for making honeycomb material may be described as follows: Spaced, substantially parallelzglue lines I0 and l are applied by glue applicators I9 andlll to each side of an elongated sheet of material i8, Y whereby the glue lines on one side of the sheetare spaced between and lie parallel to the glue lines on the, opposite side of the sheet; The glued material is fed down- 'vvaidly by driving rollers 2 I and 2 l and is lapped backv and forth. over itself by meansof a reciprocating table '3! to form a stack 68 of superposed layers of the glued material. Belt drive units 4| and I I? are provided to maintain the layers formed in thestack flat and tightly compressed together during lapping operation. A'stack of the aforesaid glued layers may be sliced or cut transversely to the direction of glue lines, and the material expanded to form a honeycomb structure such as indicated in Figs. 6 and 7.

The particular embodiment'of my invention, as; shown and described'herein, comprises a flat base piece i I, provided with rigidly attached, upwardly extending side pieces 12 which, in turn, are each provided with a plurality of; hOIiezontally and vertically disposed roller bearings, indicated at' [3 and I4 respectively, which cooperate to form a slidable guideway or trough for carriage i5. Extending vertically upwardly from the sides of base II are ,vertical studi supports l6 which are adapted to support the various parts of the machine, but, as indicated above, the drawings do not indicate all of the necessary bearing supports into which the various rotatably mounted shafts and rollers normally would be journaled.

Numeral ll illustrates a roll of flexible material such as paper, cloth, aluminum foil, fabric or glass cloth out of which the honeycomb is to be made, which said roll is rotatably supported by shaft 20. In actual practice I prefer to impregnate the roll of flexible material, particularly if it be cloth or glass cloth, with a suitable syn- "become more viscous by curingi. e., under- 1 going a chemical change; whereas still other adhesives harden by both drying" and curing' thetic resin, such as phenol formaldehyde, which can be and is preferably dried'and/or' partially cured to a relatively dry flexible state. For example, relatively soft cloth or glass cloth which upon being subjected to heat.

;: The lower partof the machine comprises, in

'additio'n'to"theiparts already identified, a depressible table3l having four corner legs 32 arranged to operat'mslidably in cylinders 33 which,

has been so impregnated and thereafter properly dried and/or partially curved acquires approxi-' mately the same degree of relative stiffness and flexibility as medium weight-craft paper Numeral I8 indicates generally that portion ofthe material which has been unreeled from 'roll 11 and which is adapted to be'substantially-continuously fed through the machine by feed driv rollers indicated at 2| and 21 I 1 Glue lines are applied to opposite sides -of sheet 18 during its traverse through the machine by glue applicatorsindicated generally-at l9 and I B and which more-specifically comprise shallow glue troughs-22 and 22 pick-up rollers 23 and 2 3 wiper blades-24'and'2'4, and applicator shafts 25 and 25 Shaft 25 is provided with a plurality of spacedannular washers 26 which are of'larger diameter than shaft 25. similarly to shaft 25 andis provided also with-a plurality of spaced'annular washers 26 but 'it is seen that WasherS 'ZS -arenOt directly aligned with washers -26 butare positioned to operate against the opposite side of the'material l8 between the latter said washers in alternates pa'ced relationship therewith. Y

In operation, troughs 22 and 22* are filled to a predetermined level with a suitable liquid adhesive, whereby rotation of pick-up rollers 23'and 23"- '(by driving means which will be described laterin more detail) pick up glue from within thetrough and transfer amountsdfthe glueto washers 26 and 26 respectively, which said washers in turn apply'glue lines Hi -and lf li to opposite sides of-the material. Because washers 26 are alternately spaced withrelation to washers '26, the adhesive is applied to each side of sheet I8 in spaced substantially parallellines'and in such manner that the glue lines on one side 'of the material-lie between the glue lines applied on the opposite'side thereof. Wiper blades "24 and 24 are adapted to scrape-excessive amounts ofgluefrom the pick-up rollers in order to prevent unduly large" deposits of glue'from'forming on the applicator washers "26 and "'26 to insure even and uniform'glue-lines'being appliedto'the sheet material. In addition,'it is Lpreferableto space adjustably by suitable bearing :supports (not shown) applicating washers 2'6 and 26 away'from pick-up rollers .23 and '23 approximately .005 'of an inch to prevent excessive amounts of glue fromformingon the side'siof the washers because of exceedingly close contact with-the pick-up rollers.

Preferably I provide an oven, indicated generally at 21, equippedwith avplurality of'infra red-lamps '28 'to apply heat to each side ofthe material to partially cure and/or dry the 'applied glue lines on the sheet I8in its passage down Shaft '25 is-formed in turn, are rigidly attached to and depend from carriage l5. Suitable compression springs 34 are disposed in cylinders 33 and are arranged to support thebottom'ends of legs 32 to bias normally the said legs and said table upwardly.

As 'hasbeen noted above, carriage I5 is positioned' sli'dably within the trough l5 formed by sides l2and horizontal and vertical bearings 13 and M. A rack 35 is attachedt'o upwardly extending side 30 of carriage l5 and'is adapted to mesh with pinion 36, which, in turn, is mounted on the end of horizontal shaft 31 leading from a conventional suitable reversing gear mechanism, indicated generally at 38.

As will be more fully explained hereinafter, rotation of shaft 31, through the pinion-rack engagement with the carriage, will cause said carriage to be moved longitudinally in'the slid able trough formed by roller bearings l3 and 14. The direction of movement of the carriage is de pendent, of course, upon the direction of rotation of shaft 31, which latter said rotational movement is governed by the reversing gear mechanism. 9

A pair of'op'positely disposed triangular-shaped belt-drive units, illustrated generally at H and 41*}, are supported by various bearings (all of which are notshown) above table 3 l. Belt-drive unitM-comprises more specifically a bottomend driving roller'42, top and-end-corner guide rollers 43 and, and a plurality of freely rotatable spaced rollers '45 mounted between rollers '42 and The aforementioned rollers 42, 43 and are provided with annular spaced grooves, such as' indicated at 41, to serve as beltguides'for belts-46, whereas rollers f45 need not 'be so grooved; Roller 42 is provided with a spur gear or pinion 5| which meshes with "an elongated gear'rack 52 provided'alongthe top'edge of'side 30 of'carriage l5. Thus'longitudinal'movement of carriage I5 and rack 52 imparts a rotarymotion to pinion SI and roller 42, which saidroller in turn frictionally-drives belts 46 in a corresponding direction; v

Belt drive unit M is constructed identically with belt drive 4!, as just described, and the corresponding parts thereof are numbered similarly to thepa rts comprising belt drive H but are sufiixedby theletterfa to distinguish themjin'thedrawings.

The feed driverollcrs' 2| and'2 l 'aboveidentified, comprise a pair of driven shafts 53 andfli3 which are provided with la "plurality of equidistantly spaced annular friction drive washers 54 and? whichare adapted'to engage frictionally opposite sides ofsheetl'il betwe'en the applied glue linesllle and l'fl thereof. Shaft 53 is'ine'ffeet acontinuationof themain'drive shaft '55,

which; in turn, may..-be.:-driven,. via pulley. and belt drive. connection .56, by a. conventionalvariable speed: motor (not .shown).: Spura gear. 58, which-is .rigidly attached to amend-of shaft. .53, meshes witha corresponding spur gear-58 pro: vided' on shaft 53 .It .is,z.therefore, seen that rotation of shaft 53 and washers 54 causes corresponding rotation of shaft. 53% and washers 5.4 in an opposite; direction, but atathe same driving Speed-1 i U I Q. f

. Bevel geariaprovided on shaft 55. meshes with bevel gear fifl; and-rotates lower. vertical shaft 6i. leading to reversing gear mechanism 38,. and bevel gear .59 also mesheswith and drives upper. verticalshait 62, which; in turn, through bevel gears 63and 64, is adapted to drive pickeup rollers 23 and 23 and glue applicator shafts 25 and 25. By driving :both the applicatingiwashers andthe pick-up rollers, uniform andconstant rotationof bothisinsured. 1'.

- Extending outwardly: xirom: reversing-. gear mechanism. 38 in a :directiontoward carriage I5. is anarm 65 (see'Figr 4). adapted .to actuate said reversing gearmechanism whenfthe arm is moved either in: the 'direction of arrow A or B, as illustrated .in Figs. 1' and. .4. More specifically, when arm 65 is: moved in the direction ofarrowA; for example, reversingi mechanism 38 is actuatedto; rotate shaitv 31 and pinion 36 in .a. direction ap-. propriate tomovecarriage .l5 longitudinallyin' thexdirection of; arrow :B,-where'as movement of arm 65. in the direction of arrow B causes'reVersinggear mechanism 38 to rotate shaftl3l in-the; opposite. direction appropriate to -'move..'carriage* l5. inthe direction of arrow A. Movement of arm- 65 isnormally accomplished through .its;1contact with; either one of. thewlugsbfifi or..6l; which said. lugs projectlaterally outwardly from carriage 4- 5 adjacent opposite ends thereof. The. manner of cooperation.- between lugs 66: and-.67? and arm 65 to" determine directional. movement of I carriage l5,,will begdescribed in.more-.?detail hereinafter;

Although thespecific operation of certain-parts. of the machine :has. already been described, the overall operationpof the-machineis as. followsi I .When shaft; 55 is; rotated, preferablyiofffof 'a' variable speed motor .(notshownl; shafts 53 V and: 53, carrying, respectively,- friction washers 54 and .545 cooperate to .unreel sheet .18 from-lrol-l lfl. and .to drive saidsheet downwardly towards table 3 l 1 Simultaneously with the rotation .otshaft 55* upper. vertical shaft 62 drives pick-up rollers: 23. and 2 3 and glue. applicators'sl 9 and 19% apply: glue lines to. opposite sides. of: the. material- -I 8' in a manner which has beendescribed above in detail. :Similarly, lower vertical shaft. BI is rotated off-of shaft 55 and, depending upon the position ofarm 65 of reversing gear mechanism 38, shaft 31 and related pinion. 36 are rotated to impart; thereby, through rack appropriate longitudi nal movement to carriage l5 and table' 3l Assuming, for example, that arm 65 is positi'oned in the direction of arrowA and'that carr'iag'e l51s being driven in the directionof arrow B as above indicated, when the-carriage has moved'su'flii cientlyfarin thej directionpf arrowflfil lug' 6;; carried'by carriage lawiuf'be brought into pon tact with projection rm 65 and tppr jf further: movement of'the carriage i'n'the' direction, of arrow B, said lug will move said arm the 'direc tion of arrowB to actuate reversing gear mechanism 38. Actuationfofthe reversinggear mech anism in this way cause reverse rotation of shaft3l I and pinion'36 to. impart a corresponding;

6 reverse movement to vcarriage l5 thedireotion of.arrow.;A.a- =:When;the.carriage and table. ha-Vebeen- .id men in the .directionpf arrow A a predetermined dish tance, contact of lug .61 WithJarm', ;will; cause the. latter ;to: move .in *the direction; of arrow. A and once-again the direction of movement ofithe carriage and tablewill be reversed; ;.-Itwil1:.thus be. seen that the i mechanical ,movementsxwhich have :been; described impart -.;--a reciprocating.- movement; to carriage -15. and table.- 3.I. .-:.with @re-. spect toathefeed rollers and beltdrive ll nits.';:z.l=-: .The -closest-point between rollers .42 and? through which -.the sheet .of material. passesis indicated at-C in Fig. 2 and'forpurposes of con.-

- drive units ll--01 4!? depending upon .the'fdirection of movementof the table. at agiven moment. For examplaifthe carriage and tableare'moving in thev'directionof arroW,- A,2thesheet of material asit iswrfedon to-. the table willi beacempressed against belt; drive :unit 11/ whereas :when the; carriage and table are moving; in: the. direction-10f; arrQW. BY, the-said-material will be compressed: upwardlyagainst belt drive unit 14L .It is-readily, understandable. that asthe .table..reciprocates. backand f or.th in reciprocal strokesfioi-Ziequal; length the sheet of materiaL-after;passingpoint C ;will be correspondingly...alternately shifted: back and forth away from said:.lapping positlon;-- and in a line of direction. or'p1ane{-lying.approxi.-. ately; 5170 the longitudinal .axis.- ofthesaid. sheet of, material at said lapping-position, and ina path parallelto the belt contact surfaces of: the bel;t; drive units. Torillustrate, .if E tabla-31 is moving in thedirectionof, arrow A, the sheet of material is correspondingly moved inrthe same direction awayr, from. :thelapping positionlCz and. along a line or plane substantially perpendicular. to the longitudinal axis .of.-..thes:material cask. it pfiSSQ ;thI'Oll h.;.rQ1k-3IS 42f andmA2 ;JrSiIIfi1ar1Y-; when the; table.=;is reciprocated to. .movein thGLdig-r;

' rectionnof arrow-B, the. material moVesLcorre-i-J spondingly, in theisame direction and: in :a line: or plane approximately p'erpendicularatothe-lone; gitudinalaxis of; the sheet, material at lapping. position Moreover, because the 1 belt units establish belt pressure contact surfacesrat least coextensive in length. tothe. length of reciprocal stroke of 5th? carriage and -table;:subs'tantiallyuniform and continuous compression throughout substantially the entire length of the staclzfc'aa nbe andis maintained on'the stack during lapping operations.

:Contim ousv shifting-of :the material back and forth with respect tolappingposition. (11in. the

1; above. described manner, causessthe sheet ot glued-material to be lappedback and forth over:

j .7 fllhe ;.operation of the various parts to drive the beltsdfi .and'46e has already been explained in some detail, wherein it was-pointed: out

that due to themesh engagement'between pinion 5|; and rack 52, rotarymoyement of rollers42 'and 43. and movement of -.be1.ts 46 and MS wa's ac' compiislied' upon. movement. or the: carnage: carrying rack 52. It is noted in this respect: that each'i time-:the i carriage. reverses its. direction; the dlrection 01: movement of. the: rollers and belts is. correspondingly effected and. thus. thevv belts: are: alwaysumovingjhi-the-samedirection as'thasheet material. beingjfed. onto. the. table or; stack; duringlappingoperations. It iszal'soi important that' the belts movezata speed .correspondingtu the. speed otfreciprocalv movement or the carriage and. corresponding. to: the; speed: that. the paper' is. being. fed. onto? the table: in orderthat the belts engage: portions; of the: top surface of; thesaid between. the glue lines; in: non-slippingengagementwith said; material; i.. e.,. the belts move. with. the paper. andstaclc andatltht:v same speed therewith toinsure that saidimaterial is notzwrinkled' on allowed. to crease. or. wavez during lapping: operations. The. driving speeds i of" the carriage. and table; feed. mechanism and belt drives; .as: well. as. the. glue: applicators, are all synchronized by'virtue oi the fact thatmove meat. of any ofisaid' parts. are dependentupom movementsofithemaindriVeLshaftJSS.

- To'illustrate, the: glue applicators and feed drives-rollers. are. driven by gear; connections di rectly: d of. shaft 62 whereas; the; carriagei and. tablezare reciprooated. by virtue. of. power trans mittedi Immushaft tillthrough reversing gear mechanism 38"and. rack;v and pinion- 35-36'..

Moreover; movement of the belt drive-f'units-is mule. directly dependent upon reciprocation of the". carriage through theirack and. pinionar.- rangement: i'i52'. Thus, when the speed of" shalt: Gliis. varied, either intentionally or by ac-- cidenh, the driving: speeds of all the: above enumerated parts are. immediately and correspondingly' affected An obvious advantage in suchzan:arrangementiofi parts is thatall ofthe mechanical elements: which act upon the sheet materialiduringthe'process do so in full'and commete-cooperationwithone. another, thereby insuringr againstthezpossibility of one moving part becoming: out of adjustment-with. relationeto' the other. parts. and: causing the: materialto' be stretched;,wrinkled;,torn, or otherwise affected adversely; v

.The action of: compression. springs. 33 actinguponithiabottoms. of legs 32 ofv table 31' are of sufiicients. strength to springs-bias: continuously the stack; 68 .011 material normally upwardly" against. the belt. drives. 41 and'i 41 to maintain theesuperposed' layers of said stack tightlycom-- pressed; together: during; lapping operations; Springer also serve to make table 3I-in efl'eota'. "floating? table", i. .e'-., asxea'ch: additional layer of materialzis addedzto. the staclr .68' the table is -depressed-.thatamuchfurther downwardly to cornpensateiorr'the: additional. thickness. ofeach said addedllayer; i

As. has been previously indicated heretoforethe plurality of belts comprising belt drive unit; l1vare alternatelyjspacedwithrespect to the plurality"offbeltsi'which xcomprise beltidrivesmut. Aavaluable; feature of the'present machine resides in, the cooperative relationship whichthe belt drive :units;hold:with respect to one another whereby they subject? stack 68'- to uniform and continuous compressional forces substantially throughout therentire length of said stack during lapping operations" clearly 'illust'rated in Fig. 5,= the. bolts; 46; offbeltdrive; unit 4! I are arrangedand;spacedrcooperativelywith resp'ect to one an--- other. (and; int relation to the. glue applicators- [9 and I3 whereby theabelts 46 operate-and bear' againsttop surfaces of; stack 68 between upward lyexpo'sedi glue: lines HI (applied: to sheet; l81by applicator 13 and directlyover'concealed glue lines Hi (appliedto sheet I81 by applicator: I89). Similarly; belts: 46 oiibelt drive unit: 41* are arrangedand. spacedcooperatively with respectt'o one another (and; to glue applicators. I Brand i901 whereby: belts. 4'5. operate on .the. topsurfaces: of: the: stack: betweenl exposed glue. lines? IO and directly over concealed glue lines In. is .seen:that;at. all times. during lapping operations substantially continuous; and: uniform pressure is being. applied. to thestack throughout. its entire. length and that. said: pressure is. applied to the top: of the. stackbetweenf exposed gl'uef lines and uponor'over concealedglue; lines in the st'ackiot glued? material.

After asufilcientnumbenot superposed: layers. of material. have been built up or: after: the material or roll I! has been exhausediandfitt is:de-- sired toibegin. operations anew; the entire carri'ageand' table carrying; the complete: stack?" may besremoved fromzthe machine bypermitting pinion; 36 to continue: to; rotatev (without actuat ing. thte. reversing gear mechanism) to drivethecarriage: completely from. without. the. machine.

To. accomplish: this: end, armliS', which" normally a'ctuates:reversingtgearmechanism 38 to.reciprocateitheicarriage andtable, may be pivotedion' hinges;..as at 69;. (Fig; 4')I in such manner. asztoi be capable'zoit being manually. lifted upwardly to avoid: striking against. lugs: 6'6 or 61: during- 1ap'-: pingoperations. To: illustrate, let. it. be that the carriage randftable; are being driven. in the direction of: arrow A and;.as hasbeen explained; projecting. lugs: 65' would=normallymove against arm? 65 to: actuate the: reversing gear: mechanisrnv and cause .th'elcarriage and table to reciprocate: in: the: opposite: direction; Itis readily. seen; howeven. that by merely liitingfupwardly arm 63* sufii'cientl'yfar." to .avoid'. contact with lug. 66, Diniorr 3 6'. will continue: to rotate in: the: same di rection. to drive the; carriage completely out of the machine: in the direction of: arrow A). at which point. the: sheet. of materiall being fedz on" the stacki may: be: severed: therefrom at apoint adiacentthelsta'ck; Simultaneously with there moval: of the' table: and; carriage: carrying complet'edsstaclo 68,.ase'cond' carriageiand' table-unit (not-shown). maytbe'zintroduc'edintotztheopposite endiofrthemachine; andzlappingz operations con-- tinuedaas before: with. the. severed end of the sheet material formingtthe bottom layer 01- a second? stack. of: material Ito. be: built. up on thenewly-introduceditable. 7

After: the stack: 68 has been removed irom the machine sufficient tim8"iSj-.a11OW8d-fOT the glue" linesdzoi'completelyharden andito bond the layers of; material firmlyztogether. The'stackmay'then be sliced transversely; into a number: of smaller pieces, andeachsaid piece'may then; .in: turn, be.

expandedby suitable meansto forma honeyr-r comb structure, such; as. indicated in' Fig, 7

Although I have described myinventiontin d'e-- tall. byway ofr example. and. for purposes: 01: clarity. of. understanding. it. is. understood that.

Thus,. it.

gitudinally of the obverse side of a 'said' sheet of named glue lines, a lappingmechani'sm co'mprisinga reciprocating member reciprocable in strokes of equal length to'lap said glued sheet of material'back and forth=over itself in'suc'cessive laps of equal length ina manner wherebyeach successive lap alternately exposes the obverse side and then the reverse side of said sheet of material to buildup a stack of superposed layers of said material, compression means comprising and uniform pressure to surfaces of saidsheet of material between exposed glue lines applied to the obverse side by said first applicator unit and over concealed glue lines applied to the reverse side thereof by said second gapplicator unit as said sheet is applied to said; stack and becomes exposed during lapping operations, the pressure contact members of said second compression unit located, spacedand arranged with respect to said first and second glue applicators to contact and apply substantially continuous and uniform presure to said sheet of material between exposed glue lines applied to the reverse side of said sheet by said second applicator and directly over concealed glue lines applied to the obverse side of said sheet by said first applicator as said sheet i applied to said stack and becomes exposed during lapping operations.

2. A machine for making honeycomb according to claim 1 and wherein said first and second compression units comprise first and second belt drive mechanisms, and wherein said pressure contact members of said first and second compression units comprise individual belts incorporated in said first and second belt drive mechanisms respectively.

3. In the manufacture of a honeycomb structure formed from an elongated sheet of flexible material the method of, applying spaced substantially parallel glue lines to the obverse and reverse sides of a said sheet of material longitudinally thereof in a manner whereby the glue lines on the obverse side are spaced alternately with respect to the glue lines on the reverse side of said sheet, lapping said sheet of glued material back and forth over itself in the direction of said glue lines in successive laps of equal length to build up a stack of superposed layers of said glued material, and simultaneously with the said lapping of the glued material continuously applying to top and bottom surfaces of said stack substantially throughout the entire length of said stack compressional forces to maintain the superposed layers of material forming said stack 10 firmly compressed together during lapping operations. v

4. In the'manufact'ure of a honeycomb structure formed from an elongated sheet of flexiblematerial the method of, applying spaced sub-p stantially parallel glue lines to the obverse and reverse sidesof a said sheet of materiallongitudinally thereof in a mannerwhereby the glue lines applied to the obverse side are spaced alternately with respect to the glue lines applied to the reverse side of said sheet, lapping said glued sheet of material back and forth over itself in the direction of said glue lines in successive laps of equal length to build up a stack of superposed layers'of said glued material, and simultaneously "with the lapping of the glued material continuously applying to top and bottom surfaces of said stack substantially throughout the entire length of said stack compressional forces to maintain the'superposed layers of ma terial forming said stack firmly compressed toe gether during lapping operations, cutting said 5. In the art of making a honeycomb structure out of an elongated sheet of flexible material the method of, applying spaced parallel glue lines to the obverse and reverse sides of a said sheet of material longitudinally thereof in a manner whereby the glue lines on the obverse side of said sheet are spaced alternately with respect to the glue lines on the reverse side of said sheet, then lapping said sheet of glued material back and forth over itself in the direction of said glue lines in successive laps of equal lengths to build up a stack of superposed layers of said glued material in a manner whereby the obverse and then the reverse sides of said sheet alternately become exposed on said stack during lapping operations, and simultaneously with the lapping of said sheet continuously applying pressure to the top surfaces of said stack throughout the entire length thereof between exposed glue lines and over concealed glue lines thereof.

6. In a method according to claim 5 the additional steps of, cutting the stack of superposed layers of said glued material in a direction transverse to the longitudinal axes of said glue lines to form a plurality of expandable slices of said stack, and then expanding the slices to form sheet of honeycomb.

'7. In a machine for making honeycomb out of an elongated sheet of flexible material the combination comprising first glue applying means to apply spaced substantially parallel glue lines longitudinally along one side of said sheet, second glue applying means to apply spaced substantially parallel glue lines to the opposite side of said sheet between said first named glue lines and substantially parallel thereto, a lapping mechanism comprising a reciprocating member reciprocable in strokes of equal length to lap said material back and forth over itself in successive laps of equal length to build up a stack of superposed layers of said material, and compression members establishing pressure contact surfaces at least coextensive in length to the length of stroke of said reciprocating member and disposed parallel to the path of movement of said reciprocating member to maintain substantially continuous uniform pressure on said stack substantially throughout the entire length of said stack.

8. A machinefor, making; honeycomb accord? ing to claim 7 and wherein the said pressure.- contact surfaces of said-compressionmembers are arranged and spacedcooperativelyand-relativelywith respect to said first and second. glue applying meansto contactisurfaces 0fs aid;sta-ck1be-.-- tweenexposed'lines of glue; and directly ovencon.- cealed linesof glueapplied bysaidfirst andsec and glueapplyingimeans.v

9. A- machine for. making honeycomb accord, ing to claim '7 and wherein! said.- compression. members comprise a plurality of, spaced. parallelbelts arranged and; constructed tocontact top surfaces of said stack throughout the. entirelength of: said. stack. during lapping; operations.

10. In asmachineffor making honeycomb-out. of an elongated sheet. of. flexible. materiah the? combination comprising means: to: apply spaced substantially parallel glue linesalong. one: side: of said sheet, means. to apply; spaced substan. tially parallel g-luerlines tether other. side-of .Sflid'. sheet between saidfirst. named: glue:- lines, and. substantially parallel thereto, atable; a feed; mechanism to feed-the. glued sheet to -said table,

means including a. driving mechanism to, cause; L

over itself in successive laps of. equal length to O build up a stack of layers of saidsheet material between said-table. and said feed mechanism. and compression members. located above.- said table establishin pressure. contact surfaces; at least coextensive. in. length; to. the: length: of. rela-:- tive, reciprocal stroke between saidzfeed: mechanism and said table with said pressure'contact surfaces disposed parallel to the table surface to maintain substantially" continuous and uniform pressure contact with top surf aces of said stack- 1 members compriseapluralityof spacedparalleh beltsarranged? and. spaced. cooperatively and; relatively with respect to saidfirst: and) second! glue applying means to. contact tOpsur-facesof said Stacie betweeni exposed. glue lines and di ,rectly over concealedglue lines thereof; and:

wherein means are. presided.- to drive:- said. belts, at. aspeedzand-ina direction corresponding-to. thespeed. and. direction of relative reciprocable: movement betweeni said table; and: said feed; mechanism.

13.- A machine-for making; honeycomb accord ing. to claim: 10.-an-d-; whereinsaid meanslincludlng-z spring, means. associatedwith, saidtable; are: pro..- vided to. normally urge" compressively' said. table upwardly towardsaid compression-members;

ROGERC;

REFERENCES GI'EED':

The followingreferences are of record in the file of" this patent? UN ITED STA'IES.- PATENTS.-

Number' Name Date:

35? 1263;885 Guttridge- Apr; 232 1918- 1',5 1'7;945 Bokum' Dec: 2; 1924 1,642,178 Schorsch- Sept. 1-3; 192? 13924;1'72 Thomson Aug; 29; 1933'- 2;482;'752 Gray' Dec; 16; 1947' 2,440;209 Redman Apr. 20; 1948" 

7. IN A MACHINE FOR MAKING HONEYCOMB OUT OF AN ELONGATED SHEET OF FLEXIBLE MATERIAL THE COMBINATION COMPRISING FIRST GLUE APPLYING MEANS TO APPLY SPACED SUBSTANTIALLY PARALLEL GLUE LINES LONGITUDINALLY ALONG ONE SIDE OF SAID SHEET, SECOND GLUE APPLYING MEANS TO APPLY SPACED SUBSTANTIALLY PARALLEL GLUE LINES TO THE OPPOSITE SIDE OF SAID SHEET BETWEEN SAID FIRST NAMED GLUE LINES AND SUBSTANTIALLY PARALLEL THERETO, A LAPPING MECHANISM COMPRISING A RECIPROCATING MEMBER RECIPROCABLE IN STROKES OF EQUAL LENGTH TO LAP SAID MATERIAL BACK AND FORTH OVER ITSELF IN SUCCESSIVE LAPS OF EQUAL LENGTH TO BUILD UP A STACK 